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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsUpdateMutex.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/StaticMutex.h"
#include "nsIFile.h"
#include "nsProfileLock.h"
#include "nsXULAppAPI.h"
mozilla::StaticMutex UpdateMutexImpl::sInProcessMutex;
bool UpdateMutexImpl::TryLock() {
if (!sInProcessMutex.TryLock()) {
return false;
}
bool success = [&crossProcessLock = mCrossProcessLock]() {
nsCOMPtr<nsIFile> updRoot;
nsresult nsrv =
NS_GetSpecialDirectory(XRE_UPDATE_ROOT_DIR, getter_AddRefs(updRoot));
if (NS_FAILED(nsrv)) {
return false;
}
nsrv = updRoot->Create(nsIFile::DIRECTORY_TYPE, 0755);
if (NS_FAILED(nsrv) && nsrv != NS_ERROR_FILE_ALREADY_EXISTS) {
return false;
}
return NS_SUCCEEDED(crossProcessLock.Lock(updRoot, nullptr));
}();
if (!success) {
sInProcessMutex.Unlock();
}
return success;
}
void UpdateMutexImpl::Unlock() {
sInProcessMutex.AssertCurrentThreadOwns();
mozilla::DebugOnly<nsresult> nsrv = mCrossProcessLock.Unlock();
#ifdef DEBUG
if (!NS_SUCCEEDED(nsrv)) {
MOZ_CRASH_UNSAFE_PRINTF(
"failed to unlock the update mutex's nsProfileLock -- got 0x%08x",
static_cast<uint32_t>(nsrv.inspect()));
}
#endif
sInProcessMutex.Unlock();
}
NS_IMPL_ISUPPORTS(nsUpdateMutex, nsIUpdateMutex)
NS_IMETHODIMP nsUpdateMutex::IsLocked(bool* aResult) {
*aResult = mIsLocked;
return NS_OK;
}
NS_IMETHODIMP nsUpdateMutex::TryLock(bool* aResult) {
if (!mIsLocked) {
mIsLocked = mUpdateMutexImpl.TryLock();
}
*aResult = mIsLocked;
return NS_OK;
}
NS_IMETHODIMP nsUpdateMutex::Unlock() MOZ_NO_THREAD_SAFETY_ANALYSIS {
// Thread safety analysis cannot make sense out of a conditional release
if (mIsLocked) {
mUpdateMutexImpl.Unlock();
mIsLocked = false;
}
return NS_OK;
}
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